Point Lobos on California’s Central Coast preserves about 80 million years of geologic history within the Salinian Block along the boundary between the Pacific and North American plates. Its oldest exposed rock, the Santa Lucia Granodiorite, formed in the Cretaceous about 79.5 million years ago deep below the surface and later became the basement beneath younger deposits. Around 55 million years ago, a submarine canyon cut into that basement and filled with sediments now called the Carmelo Formation, which contains fossils and debris from volcanic highlands. Much younger marine terraces and beach sands record coastal uplift, erosion, and continuing change into the present.